I am not sure how to attach a picture. You might need to use photobucket or something like that, maybe someone else will come along.

So, without a picture, here are some of my thoughts.

If the fitting that is leaking is glued, then the best fix is to cut apart and redo. If that is what you end up doing, make sure your new glued unions are done right so you don't have another leak. Use primer and glue and BOTH surfaces.

If the fitting is threaded, thread sealant and/or tape work well. I have been using both lately for some fussy irrigation valves and is works well. Sealant on male and female threads, tape male threads, seems to fix leaks that one or the other alone did not.